content 23-October-2017 10:05:30

History of the Milky Way and its neighbours

What will the JWST tell us about our own Galaxy and those close by? How old are the stars in our Milky Way and its neighbours - and what do these stars tell us of their origins?

Though the JWST will investigate the early Universe and the creation of the first galaxies, our understanding of this process would be incomplete without answering some of the most basic questions about the history of our own Galaxy and its neighbours.

The stars in our 'local' Universe represent a fossil record of the evolutionary and chemical history of our neighbourhood. The JWST will be able to read this fossil history for a large number of nearby galaxies, extending the work started by Hubble outwards significantly.

In addition to acting as a 'time machine' for the study of the most remote galaxies in the distant past, the JWST will also be able to decipher the history of our surroundings.

Deciphering this record is a difficult task and requires the brightness and colours of individual stars to be measured at great distances and in crowded regions. To completely understand the record of star formation in our galactic neighbourhood we must learn:

  • When did the central bulge and disc of the Milky Way form?
  • What is the age of the oldest stars in the Milky Way?
  • Did neighbouring galaxies (like the Andromeda Galaxy or the Magellanic Clouds) form in a similar way and at a similar time?
  • Did star formation in the past (when heavy elements were almost non-existent) result in the same distribution of massive and light stars that we see in star-forming regions today?


Last Update: 08 July 2003

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